Arrangement for the regulation of the frequency in frequency changers



Aug. 23, 1927.

K. HEEGNER ARRANGEMENT FORETHE REGULATION OF THE FREQUENCY IN FREQUENCY CHANGERS Filed Oct. 25, 192s INVENTOR KU RT HEEGNER ATTORNEY Patented Aug. 23 1927. UNITED STATES PATENT oFF c KURT HEEGNER, 0E BERLIN, eE iitANn'AssIeNoR TO, GE'sELLscrI ET run DRAHTLosE TELEGRAPHIE-M. 13.11., 'QF BERLIN, GERMANY, A CORPORATION'OF GERMANY.

ARRANGEMENT FOR THE REGULATION or THE FREQUENCY IN FREQUENCY cHANGERs. I v a 1 1 Application filed October 23, 1925; Serial No. 64,321, and 'in Germany October 31, 1924.

The present invention relates to the regulation of the frequency of an oscillating circuit and is designed to produce a system for automatically maintaining the frequency of that if several oscillation circuits be coupled to oneor more iron cores, while the iron is magnetized by an alternating current sup: plied from an alternator, self-excited oscillations are set up in the oscillation circuits whenever the sum totalof the natural frequencies of the oscillation circuits is equal to an even multiplepof the alternator frequency. This method, as willbenoted, is used for the production of frequencies higher or lower than'the alternator frequency. ()ne of the simplest forms of construction of" such an arrangement for oscillation generation is obtained by connecting an'1roncore to three circuits, one of which circuits has the generator frequency V7,, while the two others are oscillation circuits whose natural period is equal to and W The tuning is so chosen that the three frequencies are related by the equation 2W :W' '+lV It will be seen from this equation that the frequency of the oscillation arising in one of said circuits is dependent upon the gen erator frequency and the natural frequency of the other oscillation circuit, and that it is possible to obtain any desiredcontinual change in'the produced frequency in one of the circuits, which we will take to be the working frequency, by means of changing the natural frequency of the other circuit.

Now, the present invention consists in the application of this well-known eifect as hereinbefore described" for the purposes of frequency regulation in the frequency changer, inother words, for instance, for the object of maintaining the transn'iission frequency at a constant value. Now,the method of frequency regulation consists in that, upon the occurrence of variations in the generator frequency, the natural fre' the generator frequency. This regulation can be accomplished by that the tuning means of the auxiliary circuit, which does not" carry the useful or working frequency, .is positively coupled with the generator, so

that, upon the arising of variations inthe generatorcorresponding changes are pro duced in the tuning of the auxiliary circuit. 'The invention will be better understood from the following description when considered in connection with the accompanying drawing in which the single figure is a diagrammatic View of the apparatus. I

Referring to the drawing, K andK are two ,iron cores which are magnetized by means of an alternating current generated at G, the said cores being embraced by a common winding included in the circuit of G. The windings are so chosen that no voltages of the fundamental frequency of the generator G-areproduced. The circuit of L and the alternating current source G is completed by means of the-coil L and con denser C This circuit istuned to have the normal frequency The generating tuned circuit including the variable condenser G has the normal frequency W Another tuned circuit including the condenser 0 and having the frequency l/V is provided. W willbe considered the working frequency. A third tuned circuit which may be termed a compensating circuit is also associated with the cores K and K T1118 circuit includes the condenser C and 'is tuned to a frequency w The variable condenser C is provided with some convenient mechanical speed respons'ive device such as the fly-ball governorH shown .mthe drawing, for varying thetuning of the circult-lV in accordance with the variations of the speed of tl'i'ealternator G5 5 the system, QVllzlVfl-lV it will be seen that the frequency will remain constant as'the frequency 7 changes. This is due,

of course, to the compensating effect of the circuit lV a V V It will be understood thatthe specific form of the mechanical control for the variable condenser C is not absolutely essential to Inc the operation of this invention but rather is included merely for the purpose of illustration, and any other equivalent mechanical means or electrical means might be substituted by anyone skilled in this art without departing from the spirit of this invention. For example, the tuning of the circuit IV, might be changed by varying the self-inductance by means of a variometer in place of the variable condenser. Alternatively, an iron core coil may be used to change the selfinductance, and the variations may be obtained by means of a mechanical displacement of the iron core or by changing the magnetization of the iron core.

Having thus described my invention what I claim as newand desire to secure by Letters Patent of the United States is:

1. In a system for generating oscillations of a constant frequency, the combination of an alternating current generator, two iron cores adapted to be oppositely magnetized by said generator, a compensating oscillating circuit associated with said iron cor-es, a working oscillating circuit also associated with saidiron cores, and means to vary the tuning of the compensating circuit .in accordance with changes in the frequency of the generator whereby the tuning of the working circuit remains fixed.

2. In a system for generating oscillations of a constant frequency the combination of means for generating an alternating current, two iron cores constructed and arranged to be oppositely magnetized by said alternating current, two tuned circuits associated with said cores, the sum of the frequencies of the twotuned circuits being a multiple of the frequency of the alternating current generating means, means responsive to the variations of the frequency of the alternating current generating means to vary the frequency in one of the tuned circuits a corresponding amount,-whereby the frequency of the other circuit remains con stant.

3. In a system for generating oscillations of aconstant frequency, a circuit including an alternating current generating means and a coihtwo iron cores associated with said coil whereby the said cores are oppositely magnetized, a compensating tuned circuit associated with said cores, a working tuned circuit, the frequency of the said working circuit bearing a predetermined rclation to the frequencies of the said compensating circuit and said alternating current generating circuit,'and means rcsponaivc to a variation in one of said frequencies to automatically vary said other frequency, whereby the working frequency remains constant.

at. In a system for generating oscillations of a constant frequency the combination of an alternating current generator, two iron cores adapted to be magnetized by said generator, a tuned working circuit having a predetermined frequency, a compensating tuned circuit having a frequency which bears a predetermined relation to the frequency of the generator and the working tuned circuit, and automatic means governed by the generator to control the tuning of the con'ipensating circuit thereby maintaining said relation constant.

5. In a ystcm for generating oscillations of a constant frequency, the combination of an alternating current generator, two iron cores associated with said generator, a tuned working circuit associated with said cores, acompensating circuit associated with. said cores, and automatic means governed by the generator to control the tuning of the compensating circuit whereby the tuning of the working circuit remains constant.

6. An arrangement for frequency changing comprising a pair of iron cores, a pair of coils associated therewith and adapted to be connected to a source of alternating currents for magnetizing said cores, a tuned workingcircuit associated with said cores, a second tuned circuit also associated with said cores, the sum or the diil'erence of the tuning frequencies of said circuits being approximately equal to an even harmonic of the magnetizing frequency and means for compensating for changes in the magnetizing frequency comprising a connection between the magnetizing; source and a tuning element of said second circuit whereby the tuning of the working circuit remains fixed.

KURT HEEGNER. 

